A current device for the application of a fluid is in practice implemented as a rotatable spray gun which has a number of spray nozzles and is designed to be mounted on a robotic control device.
Spray guns are used when fluids, such as gases, liquids or plastic material, are to be sprayed or extruded onto a surface. One example of a field of application of such a spray gun is in the automobile industry, when bodies are to be surface treated or joints are to be sealed. Other fields of application are, of course, also possible. When the spray gun is used, it must be positioned carefully in relation to the surface onto which the material is to be applied. Conventional spray guns are usually furnished with a single nozzle having a fixed application direction. Redirection of the nozzle must then be carried out by turning the entire gun, which, however, takes considerable time, and can cause problems with accessibility in confined spaces. Redirection of a spray gun also places high demands on a robot's control instructions in order to achieve correct application with a high precision.
Rotating spray assemblies with several nozzles are known, for example, from PCT application Ser. No. WO 80/02278. This publication, however, shows a spray assembly with simultaneous feed to all of the nozzles, which severely limits the range of use of the assembly.
One object of the present invention is therefore to improve the accessibility, such as during extrusion or spraying, which then can proceed without the necessity for a tool change.
A further object of the present invention is to reduce the adjustment time which is necessary for an adjustment from a first spraying direction to a second spraying direction.
A further object of the present invention is to enable a changeover between different process steps, for example between spraying and extrusion, without an intervening tool change.